1. Field of the Invention
The present invention relates to a printing frequency searching method, and more particularly to a method for fast search printing frequency to present a 3D image.
2. Description of Related Art
In order to have a three dimensional image, the images received by the left eye and the right eye of an observer are different. With this kind of fine difference in the images, the observer superposes the two different images to form a three dimensional image. A lenticular lens is a lens array that uses this principle to turn a two dimensional image into a three dimensional image. At least two images are chiastically placed under the lenticular lens and the positions of the two images correspond to the lens per inch of the lenticular lens. The two images project through the lenticular lens to the left eye of the observer to present a first picture and to the right eye of the observer to present a second picture, as shown in FIG. 1. Therefore, the observer is able to see a three dimensional image through the lenticular lens by the fine difference between the two pictures.
U.S. Pat. No. 6,329,987; U.S. Pat. No. 6,026,215; U.S. Pat. No. 6,091,479; U.S. Pat. No. 6,405,464; U.S. Pat. No. 5,973,700 and U.S. Pat. No. 5,715,383 are patents using the lenticular lens in different fields to develop specific technologies. In U.S. Pat. No. 6,329,987, it utilizes a specific technology to search for a printing frequency. However, numerous drawbacks and disadvantages are encountered in the practical operation. The image frequency (VPI; view per inch) of the patent starts from 300, which leads to a consequence that the quantity required to search for the printing frequency is enormous. Therefore, the operator is unable to have the printing frequency within a short period of time. Furthermore, the only criterion in the patent is that the image frequency will be smaller than the frequency of the lenticular lens, which leads to a consequence that the operator is not able to search for the appropriate printing frequency systematically.
To overcome the shortcomings, the present invention tends to provide an improved method to search printing frequency to present a three dimensional image to mitigate and obviate the aforementioned problems.